the Occoquan River, some twelve miles from the Potomac River.

Mitchell's Ford, the Rebel center, is about three miles to the
South-West of, and about the same distance North-East from, Manassas
Junction. But it may be well, right here, to locate all these fordable
crossings of the rocky, precipitous, and well-wooded Bull Run stream,
between the Stone Bridge and Union Mills Ford. Thus, half a mile below
the Stone Bridge is Lewis's Ford; half a mile below that, Ball's Ford;
half a mile below that, Island Ford; one and one-half miles below that,
Mitchell's Ford--one mile below that.

Blackburn's Ford; three-quarters of a mile farther down, McLean's Ford;
and nearly two miles lower down the stream, Union Mills Ford.

By Thursday morning, the 18th of July, Beauregard has advantageously
posted the seven brigades into which he has organized his forces, at
these various positions along his extended front, as follows:

At the Stone Bridge, Brigadier-General N. G. Evans's Seventh Brigade, of
one regiment and one battalion of Infantry, two companies of Cavalry,
and a battery of four six-pounders.

At Lewis's, Balls, and Island Fords--Colonel P. St. George Cocke's
Fifth Brigade, of three regiments of Infantry, one battery of Artillery,
and one company of Cavalry.

At Mitchell's Ford, Brigadier-General M. L. Bonham's First Brigade, of
four Infantry regiments, two batteries, and six companies of Cavalry.

At Blackburn's Ford, Brigadier-General J. Longstreet's Fourth Brigade,